why isn't my trailblazer pulling?

your egr valve is not dis-engaging...is only supposed to engage to reduce combustion temperatures and upon de-celeration...if jammed will have you breathe your own farts...essentially.....tried to shop for you for this...you could buy one at any good autoparts store....but the links were kawaka~ pull it off and blast it clean with carburetor cleaner...use a brand new gasket to re-install it~

bench test it or the guy at the parts store can tell you if it operates normally~